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<a name="V850-Options"></a>
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<hr>
<a name="V850-Options-1"></a>
<h4 class="subsection">3.19.49 V850 Options</h4>
<a name="index-V850-Options"></a>

<p>These &lsquo;<samp>-m</samp>&rsquo; options are defined for V850 implementations:
</p>
<dl compact="compact">
<dd><a name="index-mlong_002dcalls-7"></a>
<a name="index-mno_002dlong_002dcalls-4"></a>
</dd>
<dt><code>-mlong-calls</code></dt>
<dt><code>-mno-long-calls</code></dt>
<dd><p>Treat all calls as being far away (near).  If calls are assumed to be
far away, the compiler always loads the function&rsquo;s address into a
register, and calls indirect through the pointer.
</p>
<a name="index-mno_002dep"></a>
<a name="index-mep"></a>
</dd>
<dt><code>-mno-ep</code></dt>
<dt><code>-mep</code></dt>
<dd><p>Do not optimize (do optimize) basic blocks that use the same index
pointer 4 or more times to copy pointer into the <code>ep</code> register, and
use the shorter <code>sld</code> and <code>sst</code> instructions.  The <samp>-mep</samp>
option is on by default if you optimize.
</p>
<a name="index-mno_002dprolog_002dfunction"></a>
<a name="index-mprolog_002dfunction"></a>
</dd>
<dt><code>-mno-prolog-function</code></dt>
<dt><code>-mprolog-function</code></dt>
<dd><p>Do not use (do use) external functions to save and restore registers
at the prologue and epilogue of a function.  The external functions
are slower, but use less code space if more than one function saves
the same number of registers.  The <samp>-mprolog-function</samp> option
is on by default if you optimize.
</p>
<a name="index-mspace"></a>
</dd>
<dt><code>-mspace</code></dt>
<dd><p>Try to make the code as small as possible.  At present, this just turns
on the <samp>-mep</samp> and <samp>-mprolog-function</samp> options.
</p>
<a name="index-mtda"></a>
</dd>
<dt><code>-mtda=<var>n</var></code></dt>
<dd><p>Put static or global variables whose size is <var>n</var> bytes or less into
the tiny data area that register <code>ep</code> points to.  The tiny data
area can hold up to 256 bytes in total (128 bytes for byte references).
</p>
<a name="index-msda"></a>
</dd>
<dt><code>-msda=<var>n</var></code></dt>
<dd><p>Put static or global variables whose size is <var>n</var> bytes or less into
the small data area that register <code>gp</code> points to.  The small data
area can hold up to 64 kilobytes.
</p>
<a name="index-mzda"></a>
</dd>
<dt><code>-mzda=<var>n</var></code></dt>
<dd><p>Put static or global variables whose size is <var>n</var> bytes or less into
the first 32 kilobytes of memory.
</p>
<a name="index-mv850"></a>
</dd>
<dt><code>-mv850</code></dt>
<dd><p>Specify that the target processor is the V850.
</p>
<a name="index-mv850e3v5"></a>
</dd>
<dt><code>-mv850e3v5</code></dt>
<dd><p>Specify that the target processor is the V850E3V5.  The preprocessor
constant <code>__v850e3v5__</code> is defined if this option is used.
</p>
<a name="index-mv850e2v4"></a>
</dd>
<dt><code>-mv850e2v4</code></dt>
<dd><p>Specify that the target processor is the V850E3V5.  This is an alias for
the <samp>-mv850e3v5</samp> option.
</p>
<a name="index-mv850e2v3"></a>
</dd>
<dt><code>-mv850e2v3</code></dt>
<dd><p>Specify that the target processor is the V850E2V3.  The preprocessor
constant <code>__v850e2v3__</code> is defined if this option is used.
</p>
<a name="index-mv850e2"></a>
</dd>
<dt><code>-mv850e2</code></dt>
<dd><p>Specify that the target processor is the V850E2.  The preprocessor
constant <code>__v850e2__</code> is defined if this option is used.
</p>
<a name="index-mv850e1"></a>
</dd>
<dt><code>-mv850e1</code></dt>
<dd><p>Specify that the target processor is the V850E1.  The preprocessor
constants <code>__v850e1__</code> and <code>__v850e__</code> are defined if
this option is used.
</p>
<a name="index-mv850es"></a>
</dd>
<dt><code>-mv850es</code></dt>
<dd><p>Specify that the target processor is the V850ES.  This is an alias for
the <samp>-mv850e1</samp> option.
</p>
<a name="index-mv850e"></a>
</dd>
<dt><code>-mv850e</code></dt>
<dd><p>Specify that the target processor is the V850E.  The preprocessor
constant <code>__v850e__</code> is defined if this option is used.
</p>
<p>If neither <samp>-mv850</samp> nor <samp>-mv850e</samp> nor <samp>-mv850e1</samp>
nor <samp>-mv850e2</samp> nor <samp>-mv850e2v3</samp> nor <samp>-mv850e3v5</samp>
are defined then a default target processor is chosen and the
relevant &lsquo;<samp>__v850*__</samp>&rsquo; preprocessor constant is defined.
</p>
<p>The preprocessor constants <code>__v850</code> and <code>__v851__</code> are always
defined, regardless of which processor variant is the target.
</p>
<a name="index-mdisable_002dcallt"></a>
<a name="index-mno_002ddisable_002dcallt"></a>
</dd>
<dt><code>-mdisable-callt</code></dt>
<dt><code>-mno-disable-callt</code></dt>
<dd><p>This option suppresses generation of the <code>CALLT</code> instruction for the
v850e, v850e1, v850e2, v850e2v3 and v850e3v5 flavors of the v850
architecture.
</p>
<p>This option is enabled by default when the RH850 ABI is
in use (see <samp>-mrh850-abi</samp>), and disabled by default when the
GCC ABI is in use.  If <code>CALLT</code> instructions are being generated
then the C preprocessor symbol <code>__V850_CALLT__</code> is defined.
</p>
<a name="index-mrelax-8"></a>
<a name="index-mno_002drelax-1"></a>
</dd>
<dt><code>-mrelax</code></dt>
<dt><code>-mno-relax</code></dt>
<dd><p>Pass on (or do not pass on) the <samp>-mrelax</samp> command-line option
to the assembler.
</p>
<a name="index-mlong_002djumps"></a>
<a name="index-mno_002dlong_002djumps"></a>
</dd>
<dt><code>-mlong-jumps</code></dt>
<dt><code>-mno-long-jumps</code></dt>
<dd><p>Disable (or re-enable) the generation of PC-relative jump instructions.
</p>
<a name="index-msoft_002dfloat-14"></a>
<a name="index-mhard_002dfloat-9"></a>
</dd>
<dt><code>-msoft-float</code></dt>
<dt><code>-mhard-float</code></dt>
<dd><p>Disable (or re-enable) the generation of hardware floating point
instructions.  This option is only significant when the target
architecture is &lsquo;<samp>V850E2V3</samp>&rsquo; or higher.  If hardware floating point
instructions are being generated then the C preprocessor symbol
<code>__FPU_OK__</code> is defined, otherwise the symbol
<code>__NO_FPU__</code> is defined.
</p>
<a name="index-mloop-1"></a>
</dd>
<dt><code>-mloop</code></dt>
<dd><p>Enables the use of the e3v5 LOOP instruction.  The use of this
instruction is not enabled by default when the e3v5 architecture is
selected because its use is still experimental.
</p>
<a name="index-mrh850_002dabi"></a>
<a name="index-mghs"></a>
</dd>
<dt><code>-mrh850-abi</code></dt>
<dt><code>-mghs</code></dt>
<dd><p>Enables support for the RH850 version of the V850 ABI.  This is the
default.  With this version of the ABI the following rules apply:
</p>
<ul>
<li> Integer sized structures and unions are returned via a memory pointer
rather than a register.

</li><li> Large structures and unions (more than 8 bytes in size) are passed by
value.

</li><li> Functions are aligned to 16-bit boundaries.

</li><li> The <samp>-m8byte-align</samp> command-line option is supported.

</li><li> The <samp>-mdisable-callt</samp> command-line option is enabled by
default.  The <samp>-mno-disable-callt</samp> command-line option is not
supported.
</li></ul>

<p>When this version of the ABI is enabled the C preprocessor symbol
<code>__V850_RH850_ABI__</code> is defined.
</p>
<a name="index-mgcc_002dabi"></a>
</dd>
<dt><code>-mgcc-abi</code></dt>
<dd><p>Enables support for the old GCC version of the V850 ABI.  With this
version of the ABI the following rules apply:
</p>
<ul>
<li> Integer sized structures and unions are returned in register <code>r10</code>.

</li><li> Large structures and unions (more than 8 bytes in size) are passed by
reference.

</li><li> Functions are aligned to 32-bit boundaries, unless optimizing for
size.

</li><li> The <samp>-m8byte-align</samp> command-line option is not supported.

</li><li> The <samp>-mdisable-callt</samp> command-line option is supported but not
enabled by default.
</li></ul>

<p>When this version of the ABI is enabled the C preprocessor symbol
<code>__V850_GCC_ABI__</code> is defined.
</p>
<a name="index-m8byte_002dalign"></a>
<a name="index-mno_002d8byte_002dalign"></a>
</dd>
<dt><code>-m8byte-align</code></dt>
<dt><code>-mno-8byte-align</code></dt>
<dd><p>Enables support for <code>double</code> and <code>long long</code> types to be
aligned on 8-byte boundaries.  The default is to restrict the
alignment of all objects to at most 4-bytes.  When
<samp>-m8byte-align</samp> is in effect the C preprocessor symbol
<code>__V850_8BYTE_ALIGN__</code> is defined.
</p>
<a name="index-mbig_002dswitch-1"></a>
</dd>
<dt><code>-mbig-switch</code></dt>
<dd><p>Generate code suitable for big switch tables.  Use this option only if
the assembler/linker complain about out of range branches within a switch
table.
</p>
<a name="index-mapp_002dregs-1"></a>
</dd>
<dt><code>-mapp-regs</code></dt>
<dd><p>This option causes r2 and r5 to be used in the code generated by
the compiler.  This setting is the default.
</p>
<a name="index-mno_002dapp_002dregs-1"></a>
</dd>
<dt><code>-mno-app-regs</code></dt>
<dd><p>This option causes r2 and r5 to be treated as fixed registers.
</p>
</dd>
</dl>

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